diff options
Diffstat (limited to 'ffmpeg/libavcodec/vb.c')
| -rw-r--r-- | ffmpeg/libavcodec/vb.c | 277 |
1 files changed, 277 insertions, 0 deletions
diff --git a/ffmpeg/libavcodec/vb.c b/ffmpeg/libavcodec/vb.c new file mode 100644 index 0000000..29cd104 --- /dev/null +++ b/ffmpeg/libavcodec/vb.c @@ -0,0 +1,277 @@ +/* + * Beam Software VB decoder + * Copyright (c) 2007 Konstantin Shishkov + * + * This file is part of FFmpeg. + * + * FFmpeg is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * FFmpeg is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/** + * @file + * VB Video decoder + */ + +#include <stdio.h> +#include <stdlib.h> + +#include "avcodec.h" +#include "bytestream.h" +#include "internal.h" + +enum VBFlags { + VB_HAS_GMC = 0x01, + VB_HAS_AUDIO = 0x04, + VB_HAS_VIDEO = 0x08, + VB_HAS_PALETTE = 0x10, + VB_HAS_LENGTH = 0x20 +}; + +typedef struct VBDecContext { + AVCodecContext *avctx; + + uint8_t *frame, *prev_frame; + uint32_t pal[AVPALETTE_COUNT]; + GetByteContext stream; +} VBDecContext; + +static const uint16_t vb_patterns[64] = { + 0x0660, 0xFF00, 0xCCCC, 0xF000, 0x8888, 0x000F, 0x1111, 0xFEC8, + 0x8CEF, 0x137F, 0xF731, 0xC800, 0x008C, 0x0013, 0x3100, 0xCC00, + 0x00CC, 0x0033, 0x3300, 0x0FF0, 0x6666, 0x00F0, 0x0F00, 0x2222, + 0x4444, 0xF600, 0x8CC8, 0x006F, 0x1331, 0x318C, 0xC813, 0x33CC, + 0x6600, 0x0CC0, 0x0066, 0x0330, 0xF900, 0xC88C, 0x009F, 0x3113, + 0x6000, 0x0880, 0x0006, 0x0110, 0xCC88, 0xFC00, 0x00CF, 0x88CC, + 0x003F, 0x1133, 0x3311, 0xF300, 0x6FF6, 0x0603, 0x08C6, 0x8C63, + 0xC631, 0x6310, 0xC060, 0x0136, 0x136C, 0x36C8, 0x6C80, 0x324C +}; + +static void vb_decode_palette(VBDecContext *c, int data_size) +{ + int start, size, i; + + start = bytestream2_get_byte(&c->stream); + size = (bytestream2_get_byte(&c->stream) - 1) & 0xFF; + if (start + size > 255) { + av_log(c->avctx, AV_LOG_ERROR, "Palette change runs beyond entry 256\n"); + return; + } + if (size*3+2 > data_size) { + av_log(c->avctx, AV_LOG_ERROR, "Palette data runs beyond chunk size\n"); + return; + } + for (i = start; i <= start + size; i++) + c->pal[i] = 0xFFU << 24 | bytestream2_get_be24(&c->stream); +} + +static inline int check_pixel(uint8_t *buf, uint8_t *start, uint8_t *end) +{ + return buf >= start && buf < end; +} + +static inline int check_line(uint8_t *buf, uint8_t *start, uint8_t *end) +{ + return buf >= start && (buf + 4) <= end; +} + +static int vb_decode_framedata(VBDecContext *c, int offset) +{ + GetByteContext g; + uint8_t *prev, *cur; + int blk, blocks, t, blk2; + int blocktypes = 0; + int x, y, a, b; + int pattype, pattern; + const int width = c->avctx->width; + uint8_t *pstart = c->prev_frame; + uint8_t *pend = c->prev_frame + width*c->avctx->height; + + g = c->stream; + + prev = c->prev_frame + offset; + cur = c->frame; + + blocks = (c->avctx->width >> 2) * (c->avctx->height >> 2); + blk2 = 0; + for (blk = 0; blk < blocks; blk++) { + if (!(blk & 3)) { + blocktypes = bytestream2_get_byte(&g); + } + switch (blocktypes & 0xC0) { + case 0x00: //skip + for (y = 0; y < 4; y++) + if (check_line(prev + y*width, pstart, pend)) + memcpy(cur + y*width, prev + y*width, 4); + else + memset(cur + y*width, 0, 4); + break; + case 0x40: + t = bytestream2_get_byte(&g); + if (!t) { //raw block + if (bytestream2_get_bytes_left(&g) < 16) { + av_log(c->avctx, AV_LOG_ERROR, "Insufficient data\n"); + return AVERROR_INVALIDDATA; + } + for (y = 0; y < 4; y++) + bytestream2_get_buffer(&g, cur + y * width, 4); + } else { // motion compensation + x = ((t & 0xF)^8) - 8; + y = ((t >> 4) ^8) - 8; + t = x + y*width; + for (y = 0; y < 4; y++) + if (check_line(prev + t + y*width, pstart, pend)) + memcpy(cur + y*width, prev + t + y*width, 4); + else + memset(cur + y*width, 0, 4); + } + break; + case 0x80: // fill + t = bytestream2_get_byte(&g); + for (y = 0; y < 4; y++) + memset(cur + y*width, t, 4); + break; + case 0xC0: // pattern fill + t = bytestream2_get_byte(&g); + pattype = t >> 6; + pattern = vb_patterns[t & 0x3F]; + switch (pattype) { + case 0: + a = bytestream2_get_byte(&g); + b = bytestream2_get_byte(&g); + for (y = 0; y < 4; y++) + for (x = 0; x < 4; x++, pattern >>= 1) + cur[x + y*width] = (pattern & 1) ? b : a; + break; + case 1: + pattern = ~pattern; + case 2: + a = bytestream2_get_byte(&g); + for (y = 0; y < 4; y++) + for (x = 0; x < 4; x++, pattern >>= 1) + if (pattern & 1 && check_pixel(prev + x + y*width, pstart, pend)) + cur[x + y*width] = prev[x + y*width]; + else + cur[x + y*width] = a; + break; + case 3: + av_log(c->avctx, AV_LOG_ERROR, "Invalid opcode seen @%d\n", blk); + return AVERROR_INVALIDDATA; + } + break; + } + blocktypes <<= 2; + cur += 4; + prev += 4; + blk2++; + if (blk2 == (width >> 2)) { + blk2 = 0; + cur += width * 3; + prev += width * 3; + } + } + return 0; +} + +static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, + AVPacket *avpkt) +{ + VBDecContext * const c = avctx->priv_data; + AVFrame *frame = data; + uint8_t *outptr, *srcptr; + int i, j, ret; + int flags; + uint32_t size; + int offset = 0; + + bytestream2_init(&c->stream, avpkt->data, avpkt->size); + + if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) + return ret; + + flags = bytestream2_get_le16(&c->stream); + + if (flags & VB_HAS_GMC) { + i = (int16_t)bytestream2_get_le16(&c->stream); + j = (int16_t)bytestream2_get_le16(&c->stream); + offset = i + j * avctx->width; + } + if (flags & VB_HAS_VIDEO) { + size = bytestream2_get_le32(&c->stream); + if(size > bytestream2_get_bytes_left(&c->stream)+4 || size<4){ + av_log(avctx, AV_LOG_ERROR, "Frame size invalid\n"); + return -1; + } + vb_decode_framedata(c, offset); + bytestream2_skip(&c->stream, size - 4); + } + if (flags & VB_HAS_PALETTE) { + size = bytestream2_get_le32(&c->stream); + vb_decode_palette(c, size); + } + + memcpy(frame->data[1], c->pal, AVPALETTE_SIZE); + frame->palette_has_changed = flags & VB_HAS_PALETTE; + + outptr = frame->data[0]; + srcptr = c->frame; + + for (i = 0; i < avctx->height; i++) { + memcpy(outptr, srcptr, avctx->width); + srcptr += avctx->width; + outptr += frame->linesize[0]; + } + + FFSWAP(uint8_t*, c->frame, c->prev_frame); + + *got_frame = 1; + + /* always report that the buffer was completely consumed */ + return avpkt->size; +} + +static av_cold int decode_init(AVCodecContext *avctx) +{ + VBDecContext * const c = avctx->priv_data; + + c->avctx = avctx; + avctx->pix_fmt = AV_PIX_FMT_PAL8; + + c->frame = av_mallocz(avctx->width * avctx->height); + c->prev_frame = av_mallocz(avctx->width * avctx->height); + + return 0; +} + +static av_cold int decode_end(AVCodecContext *avctx) +{ + VBDecContext *c = avctx->priv_data; + + av_freep(&c->frame); + av_freep(&c->prev_frame); + + return 0; +} + +AVCodec ff_vb_decoder = { + .name = "vb", + .type = AVMEDIA_TYPE_VIDEO, + .id = AV_CODEC_ID_VB, + .priv_data_size = sizeof(VBDecContext), + .init = decode_init, + .close = decode_end, + .decode = decode_frame, + .long_name = NULL_IF_CONFIG_SMALL("Beam Software VB"), + .capabilities = CODEC_CAP_DR1, +}; |